A federal prosecution expert told jurors this week that fireworks did not start the Palisades Fire, directly contradicting the central defense theory offered by Jonathan Rinderknecht, the man charged with igniting the most destructive wildfire in Los Angeles history.
The testimony landed during what has become a high-stakes federal arson trial in Los Angeles, where prosecutors are working to prove that Rinderknecht deliberately set the Jan. 1, 2025, blaze that later reignited and tore through Pacific Palisades. The fire killed at least eight people and destroyed thousands of structures. If convicted, Rinderknecht faces a mandatory minimum of five years in federal prison and a potential maximum of 20 years.
Rinderknecht's defense team has argued that New Year's fireworks, not their client, caused the fire. But the prosecution's expert witness dismantled that claim on the stand. Courthouse News reported that the expert testified fireworks could not account for the ignition pattern investigators found at the scene. The testimony struck at the heart of the defense strategy, which has leaned heavily on the idea that Rinderknecht simply happened to be in the area when someone else's pyrotechnics sparked the hillside.
Prosecutors have painted a far different picture. They told jurors that security camera footage pinpointed both the location and the time of the Jan. 1 ignition, and that Rinderknecht was the only person near the hilltop area that evening.
The prosecution's theory of motive is blunt. Assistant U.S. Attorney Matt O'Brien laid it out for jurors in opening statements, as AP News reported.
"He wanted revenge, revenge against society because he blamed society for all his troubles."
O'Brien told jurors that Rinderknecht called 911 sixteen times in quick succession around the time the fire started, a detail prosecutors used to place him at the scene. Investigators later seized a barbecue lighter from his car.
ATF Special Agent Michael Montevidoni testified that investigators reviewed digital records pulled from Rinderknecht's phone, email, Uber, OpenAI, and social media accounts. Among the findings: thousands of ChatGPT conversations that prosecutors say reveal anger and frustration. The prosecution has not publicly detailed the specific content of those conversations, but the volume alone became a courtroom talking point.
Defense attorney Steve Haney offered jurors a sharply different framing. Haney emphasized that Rinderknecht reported the fire himself and cooperated with investigators. The defense has suggested their client may be unfairly blamed for a blaze that later reignited under separate conditions.
"When all the evidence is in, there will be one thing missing: proof that Jonathan Rinderknecht started that fire on Jan. 1."
That argument now faces a steeper climb after the prosecution's expert testimony. The fireworks defense was the most concrete alternative explanation Rinderknecht's team had offered. With the expert's rejection of that theory on the record, the defense will need to give jurors another reason to doubt the government's case.
The prosecution's evidence package leans on a combination of physical evidence, digital forensics, and surveillance footage. The barbecue lighter, the 911 call records, and the security camera timeline form the backbone of the government's circumstantial case. Prosecutors have not publicly presented direct evidence, such as eyewitness testimony or video, showing Rinderknecht physically setting a fire.
Investigators will need to establish for jurors that the digital evidence, particularly the ChatGPT logs and social media records, connects to a clear motive rather than simply reflecting a troubled individual's online behavior. The defense can be expected to challenge the relevance and interpretation of that material as the trial continues.
Authorities have not publicly confirmed whether any forensic evidence directly links the barbecue lighter to the ignition point. That gap matters. Circumstantial cases can and do produce convictions, but each link in the chain must hold under cross-examination.
The Palisades Fire became a defining disaster for Los Angeles. The destruction of thousands of homes and the deaths of at least eight people turned a hillside brush fire into a federal case with enormous public attention. For residents who lost everything, the trial carries weight that extends well beyond the courtroom.
Rinderknecht faces a mandatory minimum of five years and up to 20 years in federal prison if convicted. The sentencing range reflects the severity of federal arson charges, particularly when a fire results in death and widespread property destruction.
The trial is expected to continue with additional prosecution witnesses. Investigators have not said whether they plan to introduce further digital evidence or additional expert testimony on fire origin analysis.
Federal arson cases built on circumstantial evidence demand precision from prosecutors. Every piece of the puzzle, from the lighter to the ChatGPT logs to the expert fire analysis, must survive defense scrutiny. The prosecution's decision to lead with the fireworks rebuttal signals confidence, but confidence is not proof.
When eight people are dead and a city is still rebuilding, the public deserves a trial that gets the facts right, not one that settles for a convenient suspect. That standard applies to both sides of the courtroom.
